Wei,
Thank you for the explanation (Offset is always the x-axis, the other
columns represent the y-axis (taken 5 independent times)).
Part of this still doesn't make sense. If I look at just read latencies
for example...am I to believe that 1916 times I had a latency of exactly
3229500 usecs?
The histogram uses buckets, so it isn't exact (which would be much more
expensive to record). And you are reading it the wrong way, you have 3M
reads taking ~1.9ms (just like you don't have 1 read using 16k sstables.
which would be a bit extreme).
On Wed, Jan 23, 2013 at 9:02 AM, Brian Tarbox
The output of this command seems to make no sense unless I think of it as 5
completely separate histograms that just happen to be displayed together.
Using this example output should I read it as: my reads all took either 1
or 2 sstable. And separately, I had write latencies of 3,7,19. And
On 2013-01-22, at 8:59 AM, Brian Tarbox tar...@cabotresearch.com wrote:
The output of this command seems to make no sense unless I think of it as 5
completely separate histograms that just happen to be displayed together.
Using this example output should I read it as: my reads all took
Thank you! Since this is a very non-standard way to display data it might
be worth a better explanation in the various online documentation sets.
Thank you again.
Brian
On Tue, Jan 22, 2013 at 9:19 AM, Mina Naguib mina.nag...@adgear.com wrote:
On 2013-01-22, at 8:59 AM, Brian Tarbox
This was described in good detail here:
http://thelastpickle.com/2011/04/28/Forces-of-Write-and-Read/
On Tue, Jan 22, 2013 at 9:41 AM, Brian Tarbox tar...@cabotresearch.comwrote:
Thank you! Since this is a very non-standard way to display data it
might be worth a better explanation in the
Indeed, but how many Cassandra users have the good fortune to stumble
across that page? Just saying that the explanation of the very powerful
nodetool commands should be more front and center.
Brian
On Tue, Jan 22, 2013 at 10:03 AM, Edward Capriolo edlinuxg...@gmail.comwrote:
This was
I agree that Cassandra cfhistograms is probably the most bizarre metrics I have
ever come across although it's extremely useful.
I believe the offset is actually the metrics it has tracked (x-axis on the
traditional histogram) and the number under each column is how many times that
value has
